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spincobra03
03-05-2006, 09:23 PM
I have been working with dan at pro dyno, he has set me up with an xcal2 and a 6lb lower pulley which will be done next saturday. My question is everyone that I see really dosent seem like they have there lowers down. It appears everyone does a 2.80 upper with the idlers, can anyone explain to me why this is, im wondering if im missing out on possible tourqe or hp

Big T
03-05-2006, 09:53 PM
Most say that the lower pulley is more difficult to install. The advantages of the lower is less belt slip and some say more low end torque. It is just alot easier to remove the upper pulley. I swapped my upper out today in 20 minutes with my brother in law.

BOOMER23
03-05-2006, 09:59 PM
I think it just because the initial cost of the uppers can be a little lower and once you get that out of the way it is easy to just buy a new lower and a new belt to go along with the upper pulley and usually extra idler setup. Plus when you up the size on the lower it is gonna be spinning your other accessories faster as opposed to a smaller upper pulley just spinning the blower faster instead of everything. I have heard that big lowers can cause a problem with the accessories but then again ive only heard this...never really heard a guy with a bigger lower say that they have actually had problems, maybe someone with one can help more cause hell i dunno, Im personally gonna go 2.76 upper first with the billetflow idlers then possibly port and go 2lb. lower....maybe i dunno. anyways good luck with your setup...nothing wrong with it im sure! never anything wrong with more boost as long as it gets tuned for it.


Ashton

Dave B.
03-06-2006, 12:34 AM
I think your guy Dan has good reasons for the way he wants to.

Heres the thing, small upper pulleys slip, some slip a lot and destroy belts, I change mine every 1000 miles if not less as i notice boost falling off,,

its now my understanding the better way to go is what hes trying to do, my problem with the lower kits is, that all do away with that extra front bearing and support, its gets rid of a whole extra crank bearing, that belt pulls real real hard against that front crank bearing,,

now a lot of folks are running lower pulleys with no problems what so ever but to me it just does not seem like a good idea, the moment someone builds a kit that does not loose that front bearing im there. the best set up for max boost over all seems to be a 2.93 upper and a 6 or 8 Lbs lower.

Hey BOOMER23,,,I also have a Billetflow 2.76 can we run a 2Lbs lower with it? I just put on a Stage 4,,

BOOMER23
03-06-2006, 01:15 AM
oh I dont even have the 2.76 done yet, im hoping it is right around the corner...to be honest i wouldnt know anything about it from experience but since you have a stage 4 port and im sure a good free flowing CAI and if you have a good HE upgrade and maybe a bigger HE tank I dont see a problem with adding a 2 lb lower now, as a matter of fact with that stage 4 port yours should be downright nasty with a 2.76 and 2lb lower cause i think it might put it in a boost range it would want to be in, or better said, it would be utilizing the added flow the port has available. Ask around some more cause i personally see no problem with it just cause you (and hopefully I soon) went small originally with the upper. I have trouble thinking the different combos can be that different if you are adding the same amount of boost, and as long as youve got belt slip under control you should be good i would think...but again this is advice from somebody who does a lot of research and not much actual doing!

NO 5 OH
03-06-2006, 01:28 AM
its now my understanding the better way to go is what hes trying to do, my problem with the lower kits is, that all do away with that extra front bearing and support, its gets rid of a whole extra crank bearing, that belt pulls real real hard against that front crank bearing

Dave what in the world are you talking about? I think you need to put the pipe down and step away from the keyboard. There is no bearing in the lower "caged" stock lower pulley itself... it's reverse threaded into the balancer. There's no adverse effect of running a lower over the stocker aside upping the boost and losing some weight :rolleyes:

Most people shy away from lowers because they cost more, are harder to install, or they've maxed out boost on an upper only car and want more. The benefit of a lower is that you can run a bigger upper and get less slip at whatever boost level you want to run, and you have the advantage of being able to change boost by changing just the lower ring as the rings are interchangeable. The only accessory ran on the blower belt is the alternator... and if you get the appropriate underdrive pulley for the alternator you won't have a problem. I've had a lower on my car since the 15,000 mile mark or so and I'm still on the stock alternator. I've ran a multitude of pulley combinations and have always used the 3.20" uderdrive alternator pulley.

A lower kit from Metco will run around 350 to 375 dollars plus shipping... install depends on who's doing it. I can do a lower install in a little less than two hours... depending on how easily the alternator cooperates with me :doubt:

I think running the lower is a better way of upping the boost... there really isn't anything gained over an upper aside from less belt slip. As I said everyone ususally goes with an upper as they're easier to change.

My .02,

Shannon

InfamousSVT
03-06-2006, 04:12 AM
Go with a lower and if you need more get a 2.93 or 3.10 upper.
A bunch of people are running the 2.93 upper and a 4 or 6lb lower.............spin the hell out of the Eaton, but just make sure you've got the cooling mods and the most important a GOOD tuner. :thumbsup:

blk04cobra1
03-06-2006, 10:20 AM
spin--Dan will set you right and like Shannon said, you'll see the same amount of boost increase and better torque numbers :thumbsup:

ps--who's doing your lower install ;)

spincobra03
03-07-2006, 12:21 AM
well theres a guy that does mostly import racing mods, but he seems real good and I went to him to get my dyno number of his mustang dyno and I emailed dan at pro dyno the numbers. Dan is sending me the tunes needed for a 6 lbs lower , and I got a bigger belt and alternator pulley. The guy at lfp set me up ...was that the way to go ????? Is there anything you guys think I should tell my mechanic...because I want him to do it right and quickly, he charges 100 per hour...ouch!!!!

spincobra03
03-07-2006, 12:29 AM
infamous what cooling mods do u think I need or anyone for that matter, and try to be specific because im a moron. lol

NO 5 OH
03-07-2006, 12:32 AM
well theres a guy that does mostly import racing mods, but he seems real good and I went to him to get my dyno number of his mustang dyno and I emailed dan at pro dyno the numbers. Dan is sending me the tunes needed for a 6 lbs lower , and I got a bigger belt and alternator pulley. The guy at lfp set me up ...was that the way to go ????? Is there anything you guys think I should tell my mechanic...because I want him to do it right and quickly, he charges 100 per hour...ouch!!!!

The LFP lower is basically a copy of the Metco lower and will work just fine. I believe the LFP lower is cheaper IIRC. Good thing you got the alternator pulley... with a six pound lower you'd be over spinning the crap out of the alternator and they aren't really cheap to replace.

If the guy that's gonna do the install charges you more than 100 dollars for the WHOLE JOB then I'd take it elsewhere. Torrey at MM Performance might charge a bit more than that... not really sure at this point as I haven't asked him ;) Hell I'd do the lower install for you for 100 dollars to be honest :D

One thing that comes to mind as far as what to tell your mechanic (I'll let one secret out of the bag here ;)) is you'll need a REALLY LONG breaker bar to break the crank pulley loose... and I've found it best for the car to be in 6th gear with the e-brake engaged. The one I use is about 4 feet long and is 12 ga. tubing. The stock crank pulley is reverse thread, so it will need to be turned clockwise to loosen. Once the pulley is broken loose from the balancer, remove all the bolts that hold the lower cage onto the front cover and THEN take the stock lower off. If you do it this way you can turn the lower off by hand.

HTH,

Shannon

InfamousSVT
03-07-2006, 01:36 PM
infamous what cooling mods do u think I need or anyone for that matter, and try to be specific because im a moron. lol
LFP Heat Exchanger or equivalent......... http://www.lightningforceperformance.com/catalog/productDetails.php?productID=1140

You will be alright with your stock radiator and stuff for now, but the HE is one I would upgrade. :thumbsup:

I've got the LFP lower pulley kit and Shannon installed mine for me.

blk04cobra1
03-07-2006, 01:38 PM
We charge $90 to SCMC members to swap out lowers :thumbsup:

spincobra03
03-07-2006, 05:13 PM
dam well I wish I didnt live in boston!!!! lol i would love to get one of you guys to change it, I have the feeling im gonna get charged 200 plus , this guy is good except he does all import stuff and has never done a cobra, but I think hes got what it takes. is the alternator pulley tough to change????

Dave B.
03-07-2006, 09:50 PM
Look,,,,Ill step away from the Key board but im not putting my pipe down,
is there not another bearing right behind the stock lower that comes off??

I thought someone told me there was a whole bracket with another bearing down there thats comes off the car?? No?? my bad if thats the case,

anyway I guess im going to go ahead and do a 2.93 ring either a 4 Lbs lower,

Now im running a 2.76 now, and If I go with a 2.93 and a 4 Lbs lower, am I going to get 3 Lbs or so more, than the 2.76 im running now without the lower?

if not then Im just going to do a 2 Lbs lower with my 2.76

blk04cobra1
03-08-2006, 08:31 AM
with your ported blower, I would say you'll see 14-15lbs with the 2.93/4lb and the 2.76/4lb maybe 16lbs...so it's up to you...if it were me, i wouldnt bother the upper and just put a 4lb lower on...see your results (power, belt slip, etc) and then see if you feel like you need to go with a slightly larger upper (ie 2.80 or 2.93) :thumbsup: ...

03slidewayzSVT
03-08-2006, 10:21 AM
go with the RR pulley with the Billetflow 4 piece idlers and a 2 or 4 lb lower and you'll have 16, 17 lb of boost... Here is a 2.8 RR pulley with idler pulley's:thumbsup: